Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Battery...Again!

If it does I'll order a home test, but I do wonder where I'd take the sample from!!

Slightly more seriously, it is clear that the Aero S4 based cars need regular significant exercise to be in prime condition.

Peter

FWIW I think it's your short daily trips to the livery yard with the bail onboard that's doing it - you will have to make sure you turn it into a 20 mile round trip
You could always put them in the back of the Sprinter if you don't fancy that.

Over time the battery is slowly but surely being discharged without proper replenishment, I've seen this happen before.

Richard,

agreed, I need a good run out every week!
So does the Morgan....

Peter, don't think that's a good result for a Modern car. There should be a better answer.

The 2 Mercedes cars can sit for a month and still start.

According to Williams Morgan the Aero cars run an "ignition off" drain of almost 0.5a... unless you turn off the "master switch" under the bonnet: all well and good, but then the radio loses its station memory and you can't run a trickle charger through the under dash socket. It has to be hard wired to the battery.

Peter, hard wire a charger connection to the battery. I have done this on my car with a Ctek unit. I used the connection wires supplied with ready fitted connectors The power socket is inside the glove box! Why? Stupid location requiring either moving or altering wiring . To use it you either keep the box door open or route a connection round and into the back of the glovebox from under the dash. Depending on the fit, the push in plug can be a bit unreliable as well. It is actually just ( I find it easier) as easy to connect up by lifting the bonnet. If you use a car cover then just lower the bonnet. On a trad the gap to the wing is plenty big enough for wires. (Humongous gap!)

That's a massive drain. Did they suggest which component is the culprit?

No, I was told that there are a number of electronic modules that remain live, which is why MMC installed the master switch.

Sorry but I don't accept a "they all do it" argument. That magnitude of standing current drain assuming constant, would never be acceptable by design and Williams should know better. Indeed it would qualify such a vehicle as not fit for purpose. It will reduce a typical new batteries full charge to 50% in less than 60 hrs. This is the generally accepted maximum discharge for a starter battery beyond which its longevity is noticeably reduced. It needs investigating by a professional.

Sorry again, but I wouldn't be complacent to your new batteries performance so far. Unless you have changed something electrically the battery demise will happen again if the car is used under the same regime. I know you are now more vigilant to this issue but popping that breaker every time after use of car should not be necessary. It would never have been designed and fitted as a regular use switch as its simply an overload breaker not a master switch! This setting aside the inconvenience of its use.

OK....do BMW that use the same engine do the same? I doubt it!
How have MMC altered the installation away from BMW standard to suit what is a different car?